Your Kingdom Come (1 Corinthians 15:20-28 (LD 48)

The Lord is the king who rules over heaven and earth.  He is the one who triumphs and has while continuing to manifest His might, His power, and the strength of His hand.  So, if this is true then why would we ask that His kingdom would come if He is strong enough to establish it?  What does the resurrection have to do with this request?  Why would the resurrection be so essential for the Christian life?